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Intelligent way of removing items from a List while enumerating in C#
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The best solution is usually to use the RemoveAll() method:
myList.RemoveAll(x => x.SomeProp == "SomeValue");
Or, if you need certain elements removed:
MyListType[] elems = new[] { elem1, elem2 };
myList.RemoveAll(x => elems.Contains(x));
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Rails DB Migration - How To Drop a Table?
...tp://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can see how to drop a table using the following approach:
drop_table :table_name
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How to convert Set to String[]?
...'s recommended. Update the answer. "Since late updates of OpenJDK 6 this call was intrinsified, making the performance of the empty array version the same and sometimes even better, compared to the pre-sized version. Also passing pre-sized array is dangerous for a concurrent or synchronized collect...
Allow multiple roles to access controller action
Right now I decorate a method like this to allow "members" to access my controller action
9 Answers
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How to break out of nested loops?
...ested loops:
use goto
use flags
factor out loops into separate function calls
Couldn't resist including xkcd here :)
source
Goto's are considered harmful but as many people in the comments suggest it need not be. If used judiciously it can be a great tool. Anything used in moderation is fun....
In Java, is there a way to write a string literal without having to escape quotes?
...ing literal with a lot of quotation marks inside it. You could escape them all, but it's a pain, and difficult to read.
8 A...
How to determine if a type implements an interface with C# reflection
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@PierreArnaud: IsAssignableFrom does eventually calls GetInterfaces, so probably your test checked the GetInterfaces first and IsAssignable after. That is because GetInterfaces caches it's results so the first invocation costs more
– Panos Theof
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How to display pandas DataFrame of floats using a format string for columns?
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As of Pandas 0.17 there is now a styling system which essentially provides formatted views of a DataFrame using Python format strings:
import pandas as pd
import numpy as np
constants = pd.DataFrame([('pi',np.pi),('e',np.e)],
columns=['name','value'])
C = constants...
Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...r: String!) -> AnyObject! // Used by the delegate to acquire an already allocated cell, in lieu of allocating a new one.
That's determined by the exclamation mark after AnyObject:
AnyObject!
So, first thing to consider is, what is an "Implicitly Unwrapped Optional"?
The Swift Programmin...
How to convert a string into double and vice versa?
... Double is a numeric data type - it does not contain any formatting. Calling [NSString doubleValue] would return 1000 because it's just a number.
– Andy
Oct 5 '08 at 12:53
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